Rosette Nebula

My first three months in Astrophotography

or how I came to love the cold, and lose feeling in my toes and fingers regularly

My name is Paul and I am trying to be an astrophotographer.  It has been 4 days since my last clear sky.

Time to document the progress that I have made with the help of the challenges set by the RAG Astrophotograhy Special Interest Group….  They have been really well set to cope with my limited kit

December meeting’s target – M31

I used my standard DSLR and a Redcat 51 to capture a widefield shot of the Andromeda Galaxy.   I used an iOptron Skyguider pro to keep me on target.  I obtained 40 90s 800 ISO subframes that were useful. Stacking was done in Deep Sky Stacker and processing was done in photoshop.

M31 – Andomeda Galaxy

As first serious efforts go, I was quite happy with that as obtaining the shots gave me an insight into may elements of acquisition and an introduction into what can be done in preprocessing and processing of images.

The discussion at the meeting in December included an introduction to Pixinsight – I had seen others use it tutorials,but thought it is a little expensive and was put off by the reports of a steep learning curve…..  But after the meeting I downloaded a trial version and started to play.  I found it logical once I realised that it is really not a single programme but an operating system for image processing…  SInce then DSS has been uninstalled and  photoshop has returned to its use in day time photography…..

January’s target – M42

Christmas eve was clear and I was able to roll out the Redcat 51 and sky guider pro, this time guided using a WO guidescope and ASi120.  I also dug out an old Canon EOS 600D from the cupboard to get it modded by Juan Fierros.  This set up is at the extreme of what the sky guider can hold, so balance and polar alignment were critical – SharpCap’s polar alignment procedure helped enormously, though I fear that I am a bit heavy handed with the set up when finding my targets…..  Anyway I was able to get a set of 90s subs before Dec drift produced noticible star trails.  Started to develop a work flow in pixinsight and get hooked!

M42 – Orion and De Mairan’s and Running Man Nebulae


I got the Astrophotographer of the year calendar for a present, and was inspired to try to emulate Ross Clark’s fab extremely widefield photo of the Orion area.  I used the modded 600D with my Samyang 135mm F2 lens and a Cokin on lens light pollution filter to take a load of very short subs at 200 ISO

February’s target – anything in Orion

WHAT A CLOUDY MONTH!  2 nights clear all month.  Probably my fault as I needed to try some more kit.  I’ve started to take narrowband images as the forthcoming new ZWO CMOS cameras are starting to get people to sell their ASI 1600’s at more and more reasonable prices.   Guess what – I got one with a filter wheel and a full set of broadband and narrowband filters.

After a lot of research  and a bit of trial and error, I found a reasonable balance between maximising exposure time, gain and limitations of the now totally at the limit skyguider to produce a first light of the Horsehead nebula.  The skyguider has been great as it has forced me to learn how to star hop, but I have been restricted to try easy to find targets!

Anyway as the moon was very close I took some subs of the horsehead nebula  in H alpha, waiting for darker skies for the LRGB….

The horsehead nebula

Then i went after another classic – The rosette in H alpha…..  42 90s subs at unity gain ( I almost sound as if I know what I am talking about!.), Well Monoceros is close to Orion…

Rosette nebula in H alpha

I am working on the oxygen and sulphur for the rosette, but these need loads more time!


So there you go, 3 months well spent I have learned loads and enjoying the cold!  Cloudy nights projects for me include a set of slides that I want to share on a load of optics questions like why are stars so big in astrophotographs?  How bad can focus be and still be good? What is this seeing thing anyway? Do I really need to guide if my mount is well calibrated?  What is an Airy ring when it it is at home and can I see one?  Watch this space and I will share a series of blogs on these plus a summary of a load of my ramblings on noise and calibration……

Clear skies.